We do not know what the topic (referred to by the pronoun "она" is. I am going to assume it is "работа", "work". If so, then the utterance:
Я бы не сказала, что она сложнее сама по себе – кому какая легче дается.
I would not say that it is intrinsically difficult. Different people find different kinds of work easier.
Here is a word-by-word breakdown:
кому--to whom, not in the sense to a specific person but in the sense "to one", "to each one"
какая--"what kind of", here serves as a sort of pronoun to refer to something of the feminine gender such as "работа". Here it means "a certain kind".
дается--yields (in the sense "The door yielded easily to the pressure of his hand."), comes, gives, responds to effort
So the literal meaning is:
To each one there is a kind of X which comes more easily.